2016-08-20 19:17:32 +00:00
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Parallel Port Devices
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=====================
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.. kernel-doc:: include/linux/parport.h
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:internal:
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.. kernel-doc:: drivers/parport/ieee1284.c
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:export:
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.. kernel-doc:: drivers/parport/share.c
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:export:
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.. kernel-doc:: drivers/parport/daisy.c
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:internal:
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16x50 UART Driver
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=================
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.. kernel-doc:: drivers/tty/serial/8250/8250_core.c
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:export:
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2022-11-02 11:48:01 +00:00
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See serial/driver.rst for related APIs.
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2016-08-20 19:17:32 +00:00
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Pulse-Width Modulation (PWM)
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============================
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Pulse-width modulation is a modulation technique primarily used to
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control power supplied to electrical devices.
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The PWM framework provides an abstraction for providers and consumers of
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PWM signals. A controller that provides one or more PWM signals is
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registered as :c:type:`struct pwm_chip <pwm_chip>`. Providers
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are expected to embed this structure in a driver-specific structure.
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This structure contains fields that describe a particular chip.
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A chip exposes one or more PWM signal sources, each of which exposed as
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a :c:type:`struct pwm_device <pwm_device>`. Operations can be
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performed on PWM devices to control the period, duty cycle, polarity and
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active state of the signal.
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Note that PWM devices are exclusive resources: they can always only be
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used by one consumer at a time.
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.. kernel-doc:: include/linux/pwm.h
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:internal:
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.. kernel-doc:: drivers/pwm/core.c
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:export:
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